1. Field of Invention
This invention relates to snorkels, specifically to such snorkels that use a dry top device for sealing the air inlet opening of the snorkel when diving beneath the surface of the water.
2. Description of Prior Art
Prior art snorkels are vulnerable to opening underwater when the swimmer orients the snorkel in directions other than vertical, especially if the swimmer exhales slightly, purges the snorkel underwater or if the pressure differential between the inside and outside of the submerged snorkel is reduced or eliminated. During such occurrences, prior art dry top devices for snorkels can become unsealed and then not automatically return to a sealed position when the snorkel is oriented in number of potential directions. This can cause the dry top to fail and the snorkel to flood.